Lightwave 2018 Node Editor - How do I achieve these effects with this beast!?!

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If you really want LW2015 type surfaces, you can change the Material type to Standard, double-click on it and the pre-2018 parameters are available, including the Reflection parameter and Texture buttons for the parameters.

mTp

Unfortunately, the render results for the same specular values using the Standard material option in LW2018 are radically different than in LW2015. Hopefully the LWG will address this since -- according to the LW2018 intro video -- the intent of Standard material was to help users of earlier versions of LW get assets rendering in 2018 more easily and match surface and texturing attributes as closely as possible.

I have to agree. I am sure I will figure it all out but for now find the whole thing a mystery. I can't even figure out what the heck a protal is or how you use it? Luckily Newtek has provided several foundation tutorials that go at explaining everything in a tight efficent maner with plenty of quick guides to get you going quickly. Ha!

I have to agree. I am sure I will figure it all out but for now find the whole thing a mystery. I can't even figure out what the heck a protal is or how you use it? Luckily Newtek has provided several foundation tutorials that go at explaining everything in a tight efficent maner with plenty of quick guides to get you going quickly. Ha!

Dude... The documentation tells you everything about what a portal is and how to use it.

Right now I am testing some interior render with Area Lights outside of the windows. They have Portal parameter checked and Light Intensity=0. Is this a correct setup for Portal Light to function properly? In this case it does not work well for me, actually it doesn’t work at all, there are no differences in render. Outside of the building is Environment Light (combined with HDRI Backdrop) for sky and Distant Light for sun. Global Illumination with Sample Backdrop is enabled. I also disabled Affect Diffuse and enabled Sample Backdrop on Environment Light.

Right now I am testing some interior render with Area Lights outside of the windows. They have Portal parameter checked and Light Intensity=0. Is this a correct setup for Portal Light to function properly? In this case it does not work well for me, actually it doesn’t work at all, there are no differences in render. Outside of the building is Environment Light (combined with HDRI Backdrop) for sky and Distant Light for sun. Global Illumination with Sample Backdrop is enabled. I also disabled Affect Diffuse and enabled Sample Backdrop on Environment Light.

That sounds very wrong . Interiors don't need Environment Lights, and you have turned off everything about your Portals. Set them to intensity 1 and Affect Diffuse.

fauxWaver \foʊ-wāv-er\, n. one who likes LightWave, but shuns car-anologies.

Thanks both of you for the tips. I am glad that this setup is wrong because Brute Force renders took hours and are still noisy *If I understand correctly Environment Lights are a substitute for the “old” Backdrop and off course they should not exist in the scene at the same time? Isn’t it the point that portals bring exterior light like some sort of environment inside the room? Is there some healthy correlation between samples on Area Lights as portals and Global Illumination Rays count?

Regarding the NewTek online docs, as someone who spent a great portion of his life as a software developer I cannot get rid of that feeling that these docs are written by someone who knows a lot about LightWave while it wasn’t checked by someone who does not know LightWave well.

Thanks for the link to further information.
On Portals a few questions.
1. Does it matter what size the portal light is?
2. Does the distance from the window of the portal light matter? (up against the window, or a mile away)
3. All I ever see as examples are one room scenes with a few tea pots on the ground. Small room scenes with shinny balls also popular. If you are working on a 300 yard rec center with 40 foot ceilings for a college, does one light work the same as several?
4. Is the portal light directional? Will it change if the area light is just facing anywhere? Will different angles of the area light change the calculation?
5. does glass material change the calculation? I am guessing I should hide the glass windows from the portal light?

Answering my own questions using the scene file downloaded here https://docs.lightwave3d.com/display/LW201Portal
1. It does matter what size the portal area light is.
2. Seems to need to be right up against the opening. So what? Almost in the place of glass window? Is there a way to turn all your glass at your openings into portal lights? That would be helpful. I guess luxegons.
3. No idea how to set up for larger spaces. I suppose a 90' x 25' of mullioned opening would require a 90' x 25' Area light. That sort of thing is never just a simple opening. Hardly ever a 30 foot room with several teapots laying about. So...don't know.
4. changing the pitch of the Area portal light changed the lighting. So...no pitch, just flat up against the window.
5. Adding a a quarter inch glass plane had no effect.
6. Turning off the textured environment seemed to have no effect.

Also Something I need help with. I opened the portal sample scene. Both the portal On and the Portal Off scenes. Then tried to turn the Portal off scene to the Portal On scene. I keep getting just a black render. I must be not turning on some obvious setting!

Well, in the sample scene, the Textured Environment gradient set up is too subtle to show a good example. It's basically pure white ranging to pure white with a really, really subtle blue.

The basic difference between a plain Area light and a Portal is that the Portal "are guides placed in indoor scenes that help the renderer to concentrate environment lighting through openings like small windows" from the documentation, here:

So if you're not seeing any substantial difference with Portal ON / OFF, the Environment isn't very differentiated. Try using an HDRI image mapped Spherically for the Textured Environment, or use Image World, or use the Gradient Backdrop that's set up in the scene. Here's the render disabling the Textured Environment and enabling the Gradient Backdrop with Portal ON:

while if you uncheck Portal, it goes back to a plain white Area light.

mTp

P.S. the link posted above has changed, the sample scene can be downloaded from the documentation page above.

To help with clarity here, the portal light *IS* a light, it's a light which samples the background, just like the environment light does, so don't use them together, unless you use object exclusions etc.

If your environment is plain white, then the results will obviously look exactly the same as a plain white area light, because that's basically what you have made.

The idea with portal lights is that area lights are much better at creating clean shadows, for interiors, than an environment light, which is better for external shots. They neither have to be super accurate nor watertight to the window, just make sure they completely cover the aperture. if you have multiple windows on a single wall, it should be fine to use a single area light to cover them all. Don't make them excessively bigger than the opening though. and make sure to set the MIS samples high enough to sample the environment cleanly. If you're using an HDRI, they will need high MIS samples.

When using a portal light, you are using it in place of another system. So don't have 'sample background' in radiosity, or in the surface settings, or you'll get both weird duplicate strength light, and noise, because both those systems cause bad noise in interiors (and hence why we have this instead). They may well be slower than the above settings, but you'll get waaaay cleaner results, which will take less samples to clean up. They are however not magical light focusing tools, or some other weird lens for rays.. they are just lights which sample the environment, and so work just like any other light.